Date: 5/1/18 9:07 pm
From: William Freedberg <4mrfish...>
Subject: [MASSBIRD] Warbler influx, and resources for predicting migration

Reports from New York show that the first major wave of warblers has
arrived there, with 20 species from Central Park today (Tuesday). WSW winds
tonight and for the rest of the week should move many of these birds into
Massachusetts. It may be a stretch for them to make it up here in one
night, but if not tomorrow, I suspect Thursday should see the arrival of
some much-awaited species. I'm by no means an expert prognosticator, but
for the first time in many days, the radar looks very promising (see: ).

A post yesterday from a birder who, in his own words, "never quite figured
out how to take advantage of radar," prompts me to post a few resources on
the subject. Radar is a powerful tool for understanding migration for
birders and scientists, and it is worth taking some time to learn how it

Birdcast ( ) is by far the simplest way of predicting
migration on a regional scale. But looking at the radar visualizations
themselves can provide more specific information, like how migrants are
interacting with a weather front, when migrants are stopping at coastal
sites and when they are continuing past the coast, and just general points
of interest like how high and how fast migrants are flying. David LaPuma
has a classic video tutorial on the subject:
Some FAQ are posted at:

I am also working on a more in-depth treatment on the subject for Mass
Audubon. The first two posts give a fairly basic overview, but if you
subscribe to the MAS bird conservation blog, you'll get updates with some
more in-depth treatment of the subject in your inbox. Links to the first
two posts are at:
and (more in-depth)

An even greater compendium of links can be found at .
Finally, for folks who want a really deep dive into how Doppler radar data
are being used by scientists, check out this compilation of (free,
complete) papers on aeroecology: .

I still have a great deal to learn about how radar works and welcome
discussions about it from folks that can teach me about it (especially if I
get anything wrong in my above-mentioned blog posts). That said, I'm
posting about it because it's an endlessly fascinating topic, and at least
merits annual mention on any birding listserv.

Good birding- get out there tomorrow and see what's up!
Will Freedberg
Belmont, for better or for worse,
Williamfreedberg at

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